A transmitting device in a wireless communication system transmits a signal over a radio frequency (RF) channel. In this case, an unexpected distortion may occur in the transmitted signal. Besides, the transmitting device may precode the signal and transmit the precoded signal to the receiving device. In order for a receiving device to receive/detect the original signal, information on state of the channel, information on interference which affect to the signal, and/or information for demodulating the transmitted signal is required. By using the information, the receiving device can correct the distortion occurred to the transmitted signal and/or obtain the original signal with a higher accuracy.
In order for the receiving device to estimate the state of the channel and/or measure the interference occurred by the other signals, accurate measurement techniques are required.